A slot for an interpolated variable is a variable name surrounded
by dollar signs. To include a literal $ in your template, use
$$. Variable names must begin with a letter and can contain letters,
numbers, _, and -.

The value of a variable will be indented to the same level as the
variable.

A conditional begins with $if(variable_name)$ and ends with $endif$.
It may optionally contain an $else$ section. The if section is
used if variable_name has a non-null value, otherwise the else section
is used.

Conditional keywords should not be indented, or unexpected spacing
problems may occur.

If a variable name is associated with multiple values in the association
list passed to renderTemplate, you may use the $for$ keyword to
iterate over them: